Abstract: A linear actuator driving device is provided. The linear actuator driving device includes an electromagnetic driving unit which makes a moving element reciprocate in response to a driving command and an offset correcting unit which corrects the driving command to carry out offset energization to make the center of reciprocation of the moving element be moved in the direction in which deviation between the center of reciprocation of the moving element and the center of the movement possible range is eliminated. The offset correcting unit is configured such that the amplitude information is acquired and, with respect to the amplitude value corresponding to the acquired amplitude information, if the movable amplitude is in a movable area insufficient condition, correction of the driving command is performed and, on the other hand, if the movable amplitude is not in the movable area insufficient condition, correction of the driving command is released.

Abstract: Startup of motor is reliably executed and sonic noise is reduced. A control circuit controls a selector to apply control to output a full-drive waveform at startup and then output a PWM modulation waveform. The full-drive waveform which is an alternating waveform in which positive and negative are inverted at 180° is output. Then, the PWM drive waveform is selected.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil with a nonconducting period inserted between conducting periods. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to a coil. An induced voltage detector detects an induced voltage occurring in the coil during the nonconducting period. A zero-cross detecting unit detects the zero cross of the induced voltage detected by the induced voltage detector. The drive signal generator estimates the eigen frequency of the linear vibration motor based on a detected position of the zero cross, and the frequency of the drive signal is brought close to the estimated eigen frequency.

Abstract: A stepping motor includes two coils. A driver circuit drives the stepping motor by setting dissimilar phases of supply currents to these two coils. One terminal of one coil is connected to ground and another terminal is set to a high impedance state, and an induced voltage generated at that coil is detected as a voltage with respect to ground. Then, in accordance with the state of the detected induced voltage, the magnitude of motor drive current supplied to the two coils is controlled.

Abstract: A stepper motor system and apparatus use a position-feedback device, which may have a resolution capability as low as 200 counts per motor shaft revolution, for misstep detection and motor step recovery. In use of the system, position deviation is computed periodically and cyclically, by subtracting the feedback position from the corresponding commanded position, to determine the load angle, implicitly, and the operating status of the motor. If the load angle is within an established allowable range of values, normal stepper operation along the programmed trajectory is maintained, without adjustment. A load angle that exceeds the limits of that range however indicates that a misstep has occurred, and the system controller initiates immediate action to recover lost motor steps, to reestablish synchronism, and to then continue toward the final target position, with minimal loss of time.

Abstract: A partial arc servomotor assembly having a curvilinear U-channel with two parallel rare earth permanent magnet plates facing each other and a pivoted ironless three phase coil armature winding moves between the plates. An encoder read head is fixed to a mounting plate above the coil armature winding and a curvilinear encoder scale is curved to be co-axis with the curvilinear U-channel permanent magnet track formed by the permanent magnet plates. Driven by a set of miniaturized power electronics devices closely looped with a positioning feedback encoder, the angular position and velocity of the pivoted payload is programmable and precisely controlled.

Abstract: A method of actuating a system comprising a movable component and an actuator configured to move the movable component comprises providing a control signal representative of a desired motion of the movable component. The control signal is supplied to one or more resonators. Each of the one or more resonators has a mode of oscillation representative of at least one elastic mode of oscillation of the system. The control signal is modified by subtracting from the control signal a signal representative of a response of the one or more resonators to the control signal. The actuator is operated in accordance with the modified control signal. Thus, undesirable elastic oscillations of the system which might occur if the system were operated with the original control system can be reduced.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil with a nonconducting period inserted between conducting periods. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to a coil. An induced voltage detector detects an induced voltage occurring in the coil during the nonconducting period. A zero-cross detecting unit detects the zero cross of the induced voltage detected by the induced voltage detector. The drive signal generator estimates the eigen frequency of the linear vibration motor based on a detected position of the zero cross, and the frequency of the drive signal is brought close to the estimated eigen frequency.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil with a nonconducting period inserted between conducting periods. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to a coil. The drive signal generating unit estimates the eigen frequency of a linear vibration motor based on a detected position of the zero cross occurring in the coil during the nonconducting period, and the frequency of the drive signal is brought close to the estimated eigen frequency. The zero-cross detecting unit sets a detection window for avoiding the detection of zero cross of voltages other than the induced voltage. The zero-cross detecting unit enables a zero cross detected within the detection window and disables a zero cross detected outside the detection window.

Abstract: A stepping motor drive device includes: a first pulse generation circuit that generates pulses at rising or falling edges of a first clock signal; a second pulse generation circuit that generates pulses at rising and falling edges of a second clock signal; a first mask circuit that outputs or masks the output of the first pulse generation circuit depending on whether the second clock signal is normal; a second mask circuit that outputs or masks the output of the second pulse generation circuit depending on whether the first clock signal is normal; a logic circuit that logically combines the outputs of the mask circuits; a step position control circuit that determines the step position of a motor according to the output of the logic circuit; and a motor drive section that supplies a current to the motor according to the output of the step position control circuit.

Abstract: A stepping motor includes two coils. A driver circuit drives the stepping motor by setting dissimilar phases of supply currents to these two coils. One terminal of one coil is connected to ground and another terminal is set to a high impedance state, and an induced voltage generated at that coil is detected as a voltage with respect to ground. Then, in accordance with the state of the detected induced voltage, the magnitude of motor drive current supplied to the two coils is controlled.

Abstract: A vibration damping apparatus including reference wave production section that produces a reference wave; a fundamental order adaptive algorithm block that calculates fundamental order adaptive filter factors from a vibration detection signal and the reference wave and produces a fundamental order vibration damping current instruction; an amplitude detection section that calculates a peak current value of the fundamental order vibration damping current instruction; and a fundamental order current excess detection section that derives a fundamental order current upper limit value from the fundamental frequency to produce a fundamental order current upper limit excess signal that is output to the fundamental order adaptive algorithm block, which revises the fundamental order adaptive filter factors in a direction in which the vibration damping current instruction is limited within a range.

Abstract: A partial arc servomotor assembly having a curvilinear U-channel with two parallel rare earth permanent magnet plates facing each other and a pivoted ironless three phase coil armature winding moves between the plates. An encoder read head is fixed to a mounting plate above the coil armature winding and a curvilinear encoder scale is curved to be co-axis with the curvilinear U-channel permanent magnet track formed by the permanent magnet plates. Driven by a set of miniaturized power electronics devices closely looped with a positioning feedback encoder, the angular position and velocity of the pivoted payload is programmable and precisely controlled.

Abstract: A method for stepping a first member relative to a second member. The method including: providing one of the first and second members with one of a plurality of pockets and movable pins offset from each other with a first spacing; providing the other of the first and second members with the other of the plurality of pockets and movable pins offset from each other with a second spacing, where the first spacing is different from the second spacing; and engaging at least one of the movable pins into a corresponding pocket to step one of the first and second members a predetermined linear and/or rotary displacement.

Abstract: A reciprocating actuator includes at least one element moving reciprocally relative to a rack, a device for driving the moving element in a driving direction, an element for returning the moving element in an opposite direction, at least one sensor for detecting the position of the moving element, and a servocontrol adapted to deliver, for each displacement cycle of the moving element in the driving direction, at least one correction signal (S5) representative of the difference between the energy imparted on the moving element during at least one preceding cycle, and the nominal energy to be imparted on this moving element to displace it exactly to its extreme set-point position, and to adjust on each cycle the control signal of the driving device according to the correction signal (S5).

Abstract: A computing unit simulates an ideal operation of a vibration excitation actuator by using at least a model operation parameter and the vibration-excitation movable mass data and calculates a parameter corresponding to acceleration/deceleration thrust for moving the vibration-excitation movable mass. A vibration isolation controller determines a control content of a vibration isolation driving unit based on the parameter corresponding to the acceleration/deceleration thrust and controls an operation of the vibration isolation driving unit so that a force canceling a reaction force, which acts on an apparatus when a vibration-excitation movable mass is moved, acts on the apparatus by moving the vibration isolation movable unit.

Abstract: An electrostatic drive includes a first electrode and a second electrode responsive to a drive signal. The drive signal includes an actuation signal constituent and a sensing signal constituent. The sensing signal constituent is at a frequency higher than a natural mechanical resonant frequency of the electrostatic drive. In response to the actuation signal constituent, displacement between the first electrode and the second electrode changes, which is evaluated by detecting a change in an electrical characteristic of the drive as a function of the sensing signal constituent.

Abstract: Increasing in size of a reaction force cancel system is suppressed. The reaction force cancel system is provided in a stage device including: a surface plate having a plurality of plate surfaces with different heights from each other, and installed on a floor via a vibration-isolating spring; and stages disposed on the plate surfaces respectively, and moving on the plate surfaces, and cancels reaction forces generated on the surface plate upon movements of the stages. In addition, the reaction force cancel system includes a first and a second reaction force canceling actuator that apply counter-thrusts to the surface plate, and a control section that controls the magnitudes of the counter-thrusts. In the reaction force cancel system, the heights of action points of counter-thrusts in the surface plate are different from each other, and the control section controls the counter-thrusts so as to counterbalance the reaction forces as resultant forces and resultant moments.

Abstract: Stabilization of a stage in a movable stage apparatus is enhanced, and increasing in size of the movable stage apparatus is suppressed. A reaction force cancel system is provided in the movable stage apparatus where a stage moves on a surface plate installed on a floor via a vibration-isolating spring, and cancels a reaction force generated on the surface plate upon movement of the stage. The reaction force cancel system includes a reaction force canceling actuator for applying a counter-thrust that is a force for reducing the reaction force to the surface plate. The reaction force canceling actuator is arranged at a lower position than a top surface of the surface plate so that the surface plate hangs over the reaction force canceling actuator.

Abstract: A mobile electronic apparatus includes a storage device for storing electrical energy and a rotating mechanism configured to energize the apparatus. The rotating mechanism includes a motor, a shaft connected to the motor, and a mass eccentrically attached to the shaft, where the motor is configured to rotate the shaft and the mass to cause the mobile electronic apparatus to vibrate when activated, where motion of the mobile electronic apparatus is configured to cause the mass and the shaft to rotate with respect to the motor, and where rotation of the shaft with respect to the motor is converted into electrical energy. The apparatus also includes circuitry for harvesting the electrical energy and for recharging the storage device with the harvested electrical energy.

Abstract: A method for position and/or speed control of a linear drive utilizing a converter having a control unit and being coupled to a motor of the linear drive. The method includes determining, in a sensor-free manner, a motor position, generating a motor position signal, generating an acceleration signal utilizing an MEMS accelerometer provided in the control unit and arranged on a moving part of the linear drive, mathematically converting the motor position signal and the acceleration signal to a speed signal, and utilizing the speed signal to control the linear drive.

Abstract: A reciprocating actuator includes at least one element moving reciprocally relative to a rack, a device for driving the moving element in a driving direction, an element for returning the moving element in an opposite direction, at least one sensor for detecting the position of the moving element, and a servocontrol adapted to deliver, for each displacement cycle of the moving element in the driving direction, at least one correction signal (S5) representative of the difference between the energy imparted on the moving element during at least one preceding cycle, and the nominal energy to be imparted on this moving element to displace it exactly to its extreme set-point position, and to adjust on each cycle the control signal of the driving device according to the correction signal (S5).

Abstract: The present invention relates to a method and a system for compensating for a position error of a step motor. A method for compensating for a position error of a step motor includes: sequentially inputting a predetermined number of a pulse as a rotator position command to a step motor driver; driving a step motor in a micro step method based on the rotator position command and a predetermined current command table; detecting an actual position of a rotator of the step motor while the step motor is being driven; calculating a position error by comparing the rotator position command and the detected actual position of the rotator; and compensating for the predetermined current command table based on the calculated position error. According to the present invention, a position error which may occur when the step motor is driven by a micro step method can be removed.

Abstract: A motor and a method for serves finding the position of an armature in relation to a stator of the motor.

Abstract: A system for determining a zero position of a yarn guide (25) of a textile winding device for cross-winding yarn into cheeses via a step motor (34). The yarn guide (25), acted upon by the step motor (34), is initially displaced in the direction of its zero position (NS) and positioned at a slow speed against a defined detent (15) downstream of the zero position (NS). Then, the step motor (34) is switched off, causing the rotor (41) of the step motor (34) to drop into one of two possible stop positions (RS1, RS2). Subsequently, the step motor (34) is switched on by an electrical current supply to its stator windings (20A, 20B) such that, when switched off, the rotor (41) of the step motor (34) is in the stop position (RS2) in which the yarn guide (25) is in its zero position (NS).

Abstract: A motor and a method for serves finding the position of an armature in relation to a stator of the motor.

Abstract: Stator position feedback controller. A first position monitoring device responds to the position of a stator supported for relative motion by a machine base. A second position monitoring device responds to the position of a carriage with respect to the machine base. An actuator is provided to move the carriage through interaction with the stator. A servo controller responds to the difference in the output of the first and second position monitoring devices to control the position of the carriage with respect to the machine base.

Abstract: An oscillation isolator for supporting an oscillation isolation platform on a pedestal includes an active oscillation isolator having a displacement generating type actuator to reduce oscillation of the platform and a displacement adjuster provided between the active oscillation isolator and the platform or the pedestal for adjusting relative displacement between the active oscillation isolator and the platform or the pedestal. The displacement adjuster has a rigidity higher than that of the active oscillation isolator and is dynamically located in series between the active oscillation isolator and the platform or the pedestal.

Abstract: The stepping motor controller comprising an excitation signal generator, a switching circuit, a PWM constant current control circuit and a current sensor further comprises a motor detector circuit that transmits a control signal for generating a constant current for a predetermined time for detecting the motor, a constant current generator that receives the control signal and generates the constant current to be supplied to the winding, a reference voltage generator that generates a reference voltage, a voltage comparator circuit that compares the reference voltage with a voltage drop at the winding, and a current value setting signal generator circuit that transforms an output of the voltage comparator circuit into a current value setting signal for the PWM constant current control circuit. An output of the current value setting signal generator circuit is connected to a current value setting terminal of the PWM constant current control circuit.

Abstract: An oscillation apparatus includes an oscillation mechanism for reciprocating an oscillating roller which can be rotated in the circumferential direction and can be reciprocated along the axial direction; an oscillation-width adjustment mechanism for adjusting the oscillation width of the oscillating roller; an oscillation-mechanism drive motor for operating the oscillation mechanism; an oscillation-width adjustment motor for operating the oscillation-width adjustment mechanism; oscillation-width controller for controlling operation of the oscillation-width adjustment motor such that the oscillation width of the oscillating roller attains a designated value; and oscillation-number controller for controlling operation of the oscillation-mechanism drive motor, on the basis of the number of revolutions of the plate cylinder, such that the number of oscillations of the oscillating roller per unit number of revolutions of the plate cylinder attains a designated value.

Abstract: A rotor composite type three-phase stepping motor having a stator consisting of two stator elements each having 6 n pieces of stator magnetic pole with Ns pieces of pole tooth formed on the tip end of each stator magnetic pole piece, and a permanent magnet held by the two stator elements therebetween, a rotor of magnetic material arranged so as to face to a periphery of the stator through an air gap, Nr pieces of pole tooth being formed on a periphery of the rotor, and exciting windings wound around each stator magnetic pole piece of the stator elements consisting of two sets of three-phase windings each wound around 3n pieces of stator magnetic pole among the 6 n pieces of stator magnetic pole.

Abstract: A rotor composite type three-phase stepping motor having a stator consisting of two stator elements each having 6 n pieces of stator magnetic pole with Ns pieces of pole tooth formed on the tip end of each stator magnetic pole piece, and a permanent magnet held by the two stator elements therebetween, a rotor of magnetic material arranged so as to face to a periphery of the stator through an air gap, Nr pieces of pole tooth being formed on a periphery of the rotor, and exciting windings wound around each stator magnetic pole piece of the stator elements consisting of two sets of three-phase windings each wound around 3n pieces of stator magnetic pole among the 6 n pieces of stator magnetic pole.

Abstract: A method for driving a linear oscillating motor and a linear oscillating motor are provided. The motor includes a fixed magnetic member, a movable member having a magnet and being supported to oscillate relative to the fixed magnetic member, a detector that detects displacement of the movable member, and a control that oscillates the movable member by sending drive current to a coil of the fixed magnetic member. The method includes controlling, during a first half-period that occurs within a full amplitude period of the movable member, the drive current based upon the output of the detector. The method also includes controlling, during a second half-period that occurs within a fill amplitude period of the movable member, the drive current based upon a fixed drive current waveform.

Abstract: In a preferred embodiment, a stepper motor control, including: a driver to drive the stepper rotor; a detector to detect a commanded step rate signal provided to the driver and to provide an output signal proportional thereto; a power control, responsive to the output signal, to provide driving power to the driver, and to increase voltage to the driver in proportion to an increase in magnitude of the output signal; and an over-current protection circuit that becomes active above a predetermined motor current level and above a predetermined commanded step rate. Voltage control can be effected either on the drive board or by controlling the power supply. An additional feature provides over-current protection for the stepper motor during a lock rotor (stall) condition. The stepper motor control produces very low levels of EMI/RFI as compared with PWM current control (chopper) drives.

Abstract: A card web comb driving system in machines for the textile industry comprng a comb structure (27) mounted in such a way as to oscillate around a resting position under the control of elastic means (23 and 24) which accumulate mechanical energy and are associated with electrical motor means (20) of the type in which the direction of rotation can be inverted with the variation of the electrical signal. The motor means (20) is associated with a sensor (31) of the instantaneous angular position of the shaft (30) of the motor (20) and consequently of the instantaneous angular position of the comb structure (23, 26 and 27). The sensor (31) is connected to the power supply (21) of the motor (20) in order to establish a persistent oscillatory condition on the movable element of the motor (22) and consequently on the comb structure. The motor (20) can be represented by a brushless type motor or by a direct current motor with a constant excitation field.

Abstract: A motor control circuit for an autofocus unit which microsteps a stepping motor to turn a rotor and drive a focus lens, which circuit has a memory which stores data on current values of a plurality of phases at rotation-stopping positions of the rotor, a drive circuit which energizes the phases based on the current data output by the memory, and an address generator which reads out the current data of the memory, the address generator generating an address which makes an inclination of a path of a rotational angle with respect to a time axis smoother at a switching point of direction of rotation of the rotor, whereby the wobbling of the focus lens becomes gentler and the vibration and audio noise can be reduced.

Abstract: DC power is supplied to an induction motor for a compressor by switching ON/OFF in response to a modulated voltage waveform obtained from modulating waves which are used for generating AC power for energizing an induction motor and a carrier wave according to PWM theory. The compressor has a compressing element rotated by the induction motor, and the modulating wave is corrected according to a rotational angle of the compressing element. A sine wave having the same frequency as the modulating wave is added to the modulating wave, and a phase of the sine wave is controlled so that a maximum value of the sine wave corresponds to the compression stage of the compressing element. Thus, a rotation speed of the compressing element is constant in a suction stage and a compression stage.

Abstract: An apparatus for controlling an operating stroke of a reciprocating member to be reciprocated by a drive motor. The apparatus includes an encoder adapted to generate pulses each of which corresponds to a predetermined incremental distance of movement of the reciprocating member, a counter for counting the pulses during movement of the reciprocating member in a forward direction, a device for converting the operating stroke into the number of the pulses corresponding to a multiple of the incremental distance of movement, and a residual distance which is a difference between the operating stroke and the multiple, a device for converting the residual distance into a corresponding residual time, and a device for commanding the drive motor to stop an operation thereof causing a further forward movement of the reciprocating member, when the residual time has elapsed after a count of the counter is equal to the above-indicated number of the pulses.

Abstract: This invention is directed to an actuator which is particularly adapted among many other possible uses, or use in adjusting the configuration of deformable mirrors.

Abstract: There is disclosed a constant amplitude controller with feedback control for a vibratory feeder apparatus wherein a controlled rectifier is used to rectify the A.C. line voltage applied to the feeder solenoid and to control the voltage to the feeder solenoid. Triggering of the controlled rectifier is accomplished by a bias control signal which is composed of an A.C. phase shift voltage superpositioned by a variable D.C. bias voltage. Mechanical coupling is provided between the solenoid and a transducer which provides feedback to control logic circuitry. In the control logic circuitry, the signal received from the transducer is compared with a signal received from an operator adjusted potentiometer. In this manner, the desired amplitude of the vibrator apparatus is compared with the actual amplitude of the vibrator apparatus and, if there is a discrepancy, the control logic circuitry modifies the amount of control voltage being transferred by the controlled rectifier.

Abstract: According to one feature a bearing-free oscillation motor, e.g. for driving an optical scanner or chopper comprises a torsion shaft fixed at one end for rotational oscillation about its axis, a rotor support member substantially more rigid in bending than the torsion shaft attached to the free end of the shaft and extending back therealong, a magnetically interactive rotor rigidly joined to the support member at the midlength of the torsion shaft, and a magnetically interactive stator adjacent the rotor for inducing rotational oscillation of the rotor, the torsion shaft and the rotor support member cooperating to provide a stiff system in bending. Preferably the rotor torsion shaft and rotor support member assembly are cooperatively constructed to restrain the rotor, in response to radial forces acting on it, to substantially translational motion without tilting of the rotor or the attached mirror or other device.